Remember that the Canon 70-200mm f/4.0 L is as good a lens as there is for it's focal length and aperture.

That said, there are good lenses available for the Olympus in the same general range. Probably the closest match woud be the Olympus 50-200mm f/2.8-3.5, which runs ~$830. Compare that to ~$580 for the 70-200mm f/4.0 USM, or perhaps more appropriately, ~$1,100 for the 70-200mm f/4.0 IS USM.

And remember that the Olympus 50-200 f/2.8-3.5 is actually a faster lens than the Canon 70-200mm f/4.0 L.

Looks like the Olympus 50-200mm f/2.8-3.5 isnot as goodfrom the Canon 70-200 f4 both in terms of vignetting and sharpness. Too bad.

Not that simple I'm afraid...

1. You can't cross compare MTF data on photozone since they only work within a family of body - That's how the IMATEST work! (otherwise Nikon lenses are always superior to Canon lenses according to MTF from photozone as well) :-):lol::G

2. You are comparing apple and oranges:
-> The Oly is a 2x so at a particular focal lenght you have a higher magnification than a Canon, so a 200mm is actually a 400mm lens i.e. the Oly 50-200 has a longer reach than the 70-200L
Ditto with the vignetting the Oly is as good if not better than the L @ f/4 (the L does not go to f/2.8 for example) and see at 50 where the WA count most the Oly is superior...

http://www.photozone.de/8Reviews/lensFAQ.htmQ: Are the figures comparable between cameras or different systems ? It depends on the similarities between the image sensor system. A sensor SYSTEMcontains the image sensor with or without micro-lenses, an IR filter, a low-pass (Moire) filter and the signal processing. As you can imagine the output quality is largely dependent on the whole chain on not just on the amount of megapixels. The different output quality between the Canon EOS 350D and the Olympus E-300 is a good example (despite a 8MP sensor). The tests are a good guidance for the lens quality as long as you compare the results WITHIN a test group (e.g. Canon). Here're a few tendencies:

[*]the Pentax results are a bit steeper (sharper and softer results are more pronounced). The tangentially resolution is a bit favored due to the extremely weak vertical AA filter. [/*][*]the Canon results tend to be a bit better at the extreme borders due to the smaller sensor [/*][*]the Olympus results are comparatively weak due to the aggressive AA filter on the E-300 Q: Why are the quality ratings different from system to system ? As mentioned above the lens quality is affected by the sensor "system". Every additional step in the pipeline decreases the output quality, specifically the low-pass filter in front of the sensor. Assuming you mount the same lens on different system its maximum resolution will vary according to the max. quality of the sensor system. There're also evolutions regarding the RAW converter quality so more recent system tests starts can benefit from this - e.g. Canon/Olympus RAWs are/were converted using ACR 3.2 whereas Pentax/Sony RAWs are/were converted via ACR 3.7 and there was an increase in converter quality with ACR 3.4). This must all be taken into account regarding the rating system.[/*]

My priority is using a lens like the Canon 70-200 f4 L because I like so much the pics I see on the net.

Now the Oly E510 has everything I need, except it looks like I cannot plug the above mentioned lens to it.

Is there any lens of the sameBUILD QUALITYand SHARPENSS for the same price for the E-510 ?

The 70-200 f4 is possibly the best mass produced zoom lens optically. That of course is if we are talking a good copy. There simply is no weaknesses.

I have the Oly 50-200. It is certainly a brighter lens. It has a weak area in the vignetting area. Its a bit strange in that it seems (in my experience) to peak somewhere just under 100mm and not at some extreme in the zoom range. With that one flaw, which is easily corrected in post, it is a very good lens.

So there you have it, straight from an Olympus owner. The 70-200 f4 is optically better than the 50-200, but it isn't as bright.

I would say the 50-200 is optically better than the 70-200 f2.8, but not as bright. As a whole, I believe the Olympus Zuiko lens lineup is consistently good. There really aren't weak lenses in the lineup and you don't have to worry about bad copies. Others are free to disagree, but I think they are the best zoom lineup of any manufacturer.

IMO you're still comparing apple and oranges...
The 50-200mm f/2.8-3.5 is not equivalent to the 70-200L f/4!
-> A 35-100 f/2 or a 40-150 f/3.5-4.5 is more like it

The 50-200 is more in line with the 100-400L IS ($1500) in term of reach @ $850 (and the IS is built into the camera) but it's more than a stop brighter!

Yes, OlympusdSLRs are2x Crop Factor cameras, so the Olympus 50-200 is the 35mm equivalent of a 100-400mm lens.

But Canon dSLRs are 1.6x Crop Factor cameras, so the Canon 70-200 is the 35mm equivalent of a 112-320mm lens.

So while the 40-150 might be a close match (35mm equiv: 80-300), the 35-100 (35mm equiv: 70-200) is nowhere near the Canon 70-200mm (35mm equiv: 112-320). And while the 40-150mm f/3.5-4.5 might be a close match in both focal length and aperture, it has beenreplaced by the 40-150mm f/4.0-5.6, which is not a close match in aperture. And while the 40-150mm f/3.5-4.5 is still available in some stores (and cheaper than it's replacement), remember that we'd becomparing it to one of the finest lenses of its kind, and the 40-150 just doesn't measure up.

That's why I started with the 50-200, not the 40-150, and hadn't even considered the 35-100.

springfldr, please, why could I have a bad copy from Canon and not from Olympus ? Hey, I am not starting a war, it looks like you know what u r talking about, so your opinion is important to me.

Thx

Phil

Its a subject that is sensitive to some around here. I'll try to tread lightly.

Olympus is different from the rest in that they decided to do an entire re-design of their lenses when they began digital photography. Their lenses have a "near telecentric" design and throws an image circle only large enough for the 4/3 sensor.

The others chose to use legacy lenses, designed for 35mm film. If they were to design such a lens with a telecentric design, the lens mount would need to be the approximate diameter of a howitzer bore and the result would more resemble a medium format camera than a regular SLR.

Telecentric design, if I understand correctly, are easier to maintain quality as they are less sensitive to optical alignment of the lens elements. This, combined with a company that makes its main profits as a medical equipment manufacturer, leads to fewer lenses leaving the factory withoptical flaws.